[llvm] [TextAPI] Add support to convert RecordSlices -> InterfaceFile (PR #75007)

[Cyndy Ishida via llvm-commits]

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@@ -14,6 +14,7 @@
 #ifndef LLVM_TEXTAPI_RECORD_H
 #define LLVM_TEXTAPI_RECORD_H
 
+#include "llvm/ADT/MapVector.h"
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cyndyishida wrote:

Yes, it was transitively included before in `RecordSlice.h` but is actually used in this file, so I moved it. 

https://github.com/llvm/llvm-project/pull/75007